Results 11 to 20 of about 1,007,156 (143)
Magnetization Dynamics Control for Noise Reduction in Fluxgate Sensors
ABSTRACT Fluxgate sensors are indispensable for the detection of weak magnetic fields. However, their noise performance remains constrained by an incomplete understanding of the interplay between the high‐frequency magnetization dynamics of the core material and the overall sensor behavior.
Chunyang Mu +11 more
wiley +1 more source
Enhanced Magnetocaloric Effect in Tb‐Co‐Ni Magnets via Chemical Pressure
ABSTRACT Magnetic refrigeration materials are significantly needed in versatile modern industries, including scientific research, aerospace, and health care, due to their potential applications in gas liquefaction and storage. Herein, a significantly enhanced magnetocaloric effect with a suitable operation temperature range of 53–114 K and a giant ...
Lei Xi +11 more
wiley +1 more source
ABSTRACT The composition and structural characteristics of metacomposites are crucial for tuning their negative electromagnetic parameters; however, the lack of a clear structure–property relationship severely limits their application in dielectric and magnetic fields.
Chunyuan Deng +9 more
wiley +1 more source
本文在主动冷却发动机三维瞬态耦合传热分析和热结构响应分析基础上,获得了温度场和应力场;分别分析了温度场、应力场及其耦合效应对发动机振动模态的影响。模型中考虑了温度效应造成的材料性能下降对刚度的影响,并引入由热应力引起的初应力附加刚度矩阵和由热挠度引起的初位移附加刚度矩阵。本文还考察了发动机振动模态随结构厚度变化规律。研究表明,温度引起的材料机械性能退化使得发动机各阶频率都随之下降,32s时刻一阶频率比冷态时下降了约9%;热卸载效应使得热应力对振动模态的影响比较复杂 ...
纪科星, 黄晨光, 宋宏伟
core +2 more sources
温升是影响油浸式变压器正常运行的重要因素,为了得到变压器的温度场分布,提出一种基于混合方法的多物理场计算方法。对于油浸式变压器流体场和温度场的强耦合问题,混合方法考虑了温度对媒质物性参数的影响,采用迎风有限体积法和迎风有限元法依次计算流体场和温度场,即流体场和温度场依次循环求解,最终得到油浸式变压器启动过程瞬态温度场和稳态温度场。为了验证文中算法的有效性,采用换流变压器二维简化模型,分别采用文中方法和多物理场仿真软件Comsol计算了常温下的稳态温度场,计算结果验证了混合方法的准确性和有效性 ...
刘刚 +4 more
doaj
环氧树脂在直流电场下易于积聚电荷造成局部电场畸变,进而诱发沿面闪络。文中建立了考虑离子产生、复合、迁移和扩散过程的电荷积聚模型,并在模型中计及了电导率的温度特性。研究了不同温度下气固界面电势、电场、电荷的分布及功率损耗变化,分析了温度对电荷行为和电场畸变率的影响。结果表明:表面电荷密度随温度升高而增大,三结合点处电荷密度最大;温度对切向电场的影响更大,随温度升高,电荷积聚的主要方式由表面传导向体传导转变;适当升温可以提高表面电荷积聚和消散速率,但高温会使表面电荷密度和泄漏电流增大,进而加剧畸变和损耗 ...
谢子豪 +5 more
doaj
ABSTRACT Improving catalytic activity for volatile organic compounds (VOCs) oxidation and enhancing water‐tolerance stability remain challenging in practical applications. Herein, a composite catalyst integrating Pt/CoOx‐NiOx mesoporous nanorods (MNRs) with a phenyltriethoxysilane (PhTES)‐modified surface was fabricated via a facile route for toluene ...
Jiaqin He +13 more
wiley +1 more source
近年来人们在激光冷却和捕获原子方面取得了辉煌的成就,对捕获的冷原子团温度、密度的精确测量也成为一个重要的研究课题.在冷原子温度测量中需要在较短时间内(最长不超过几个毫秒)迅速关断俘获冷原子的磁光阱(包括磁场和光场).作者针对时间飞行法测量冷原子温度对光场和磁场的关断要求,设计并制作了一种简单、实用的可调脉冲延时和脉宽的脉冲发生器,应用其产生的脉冲在较短时间内有效地关断磁场和光场,达到冷原子温度测量的要求.
WUYan(吴艳) +3 more
doaj +1 more source
ABSTRACT Dielectric polymers commonly suffer from severe performance degradation above 150°C, hindering advanced power systems. Herein, we demonstrate a polyetherimide (PEI) nanocomposite that overcomes this by mimicking the gradient architecture of nacre and bamboo, incorporating a continuous vertical gradient of fluorinated boron nitride nanosheets ...
Jian Wang +8 more
wiley +1 more source
采用等参元有限元法,对SF6、220kV电流互感器内部三维温度场进行了数值计算.在三维温度场的计算中,采用等参坐标变换、自动剖分等手段,给出了一种复杂结构中三维温度场的计算方法.确定了互感器内部最高温度,为SF6互感器内部绝缘温升设计提供了重要的温度场数据.
齐伟夫, 王尔智, 迟永久
doaj

